The present invention relates to a detachable balloon catheters with two self-sealing valves and, in particular, to a detachable balloon with two self-sealing valves for blocking or occluding a blood vessel and thereby preventing liquid flow through the blood vessel after the balloon is inflated. The present invention is particularly useful for blocking fluid flow in a region of a blood vessel in front of a diseased part of the blood vessel.
It has become rather routine procedure to use balloons or stoppers to block or occlude blood vessels in certain types of cardiovascular surgery and medical treatments. For example, it is known that a cancer, once developed in a vein, tends to grow gradually by stealing nutrients from the vein. The growth of such a cancer can be inhibited by placing a stopper in the blood vessel so as to inhibit the flow of nutrients to the cancer.
A conventional process of positioning a stopper in a blood vessel includes introducing a stopper into a catheter, forcing a wire tip into the stopper, positioning of the catheter in the region of the blood vessel just before the cancerous part, and withdrawing of the stopper from the catheter by the use of the wire to ensure that the diseased part will be fully sealed or blocked.
Another process involves the steps of attaching a balloon to the tip of a guide wire, the balloon having a check valve mounted on its side for connection with the catheter, pushing the balloon into a blood vessel and positioning the balloon at the area to be sealed, inflating the balloon at the area, and then separating the balloon from the guide wire and the catheter, so that the balloon remains at the area.
One problem with such processes is that they require the use of blood flow for guidance of the balloon to a desired position and, accordingly, the positioning of the stopper is limited by movement of the blood. Therefore, it is very difficult to guide the balloon to the desired position, and such an operation requires a high level of skill.
Another problem with such procedures is that it is very difficult to control the force required to separate the balloon from the wire and catheter. As may be appreciated, if this force is too great, the balloon may be dislodged or repositioned in the blood vessel during detachment of the catheter and guide wire. On the other hand, if the force required to separate the balloon from the catheter and guide wire is too small, the balloon may be prematurely detached during the positioning of the balloon in the blood vessel.
Still another problem with such processes is that if a non-solidifying filler material, such as a saline solution, is used to inflate the balloon, leakage of this material often occurs through the seal of the mouth of the balloon when the catheter and/or wire is separated therefrom.
In this connection, after his elaborate studies for a solution to such problems, the inventor has devised an improved apparatus which can easily position a balloon at an appropriate location in a blood vessel and which includes an improved balloon.
Accordingly, an object of the present invention is to provide the balloon which can be used together with a catheter and wire for permanent occlusion of a blood vessel, where the catheter and guide wire can easily be detached from the balloon after inflation of the balloon and where, prior to the inflation of the balloon, the catheter, guide wire and balloon provide an improved system for guiding the balloon to a desired position within the blood vessel.
Another objective of the present invention is to provide a balloon with two self-sealing valves of improved construction.